This is a 6 month multicenter follow-on study to continue to evaluate the effects of oxandrolone on the strength of boys with DMD. All boys who have participated in the original study will be eligible with those who were on the oxandrolone, continuing and those on placebo will begin to receive oxandrolone. The final observations made for the double-blind study will serve as the initial visit for the open label study. The boys will return for assessment of strength, function and pulmonary function at 1 month, 3 months and 6 months. The boys will be evaluated for adverse experiences including a routine study of blood work, at each visit. Wrist x-rays to assess bone maturation will be repeated at the 6 month visit. Predisone is the only alternative drug available and it will not be allowed in this study. Prednisone has side effects that limit its usefulness and we are seeking a safer drug that has the same benefit.